1. Field of the Invention
The present invention relates to a semiconductor device and method for manufacturing the semiconductor device, and particularly to a package for the semiconductor device.
2. Description of the Related Art
High density mounting of semiconductor devices has been advancing in recent years, and the main focus has been on semiconductor devices such as chip size packages.
As an example of a chip size package structure semiconductor device, Japanese Patent Application Non. Hei 11-102599 discloses a semiconductor device having a semiconductor element thickness of less than 200 xcexcm and a large ratio of resin compared to the semiconductor elements, in order to solve a problem where cracks arise at a joining section between the semiconductor device and a mounting substrate due to differences in the thermal expansion coefficients of the semiconductor elements and the mounting substrate.
Also, Japanese Patent laid open No. Hei. 8-64725 discloses a chip size package where sealing resin is formed on a circuit formation surface of a semiconductor element and a surface opposite the circuit formation surface, and warping of the wafer is prevented.
In a semiconductor device having the most recent chip size package structure as described above, in order to stop cracking at a junction section between the semiconductor element and the mounting substrate, the trend has been to make the thickness of the semiconductor element thin, and make a proportion of resin large compared to the semiconductor element.
However, if the thickness of the semiconductor element is made less than 200 xcexcm and the ratio of the thickness of the semiconductor element to the thickness of the resin becomes small, in the case where resin is only formed on the circuit formation surface side of the semiconductor element, warping of the wafer occurs even for individual semiconductor elements obtained by dividing the wafer.
In the semiconductor device of Japanese Patent Laid-open No. Hei. 8-64725. There is also a problem of damage to the wafer at the time of conveying, when the thickness of the wafer is less than 200 xcexcm, if resin sealing is carried out after grinding the rear surface of the semiconductor wafer.
The object of the present invention is to provide a chip size package structure semiconductor device having semiconductor elements of less than 200 xcexcm in thickness, which can be favorably mounted in a mounted substrate.
Another object of the present invention is to provide a manufacturing method for a chip size package structure semiconductor device that has sealing resin formed on both surfaces of a semiconductor element, and particularly a method of manufacturing a thin semiconductor device in which the semiconductor element has a thickness of less than 200 xcexcm.
In order to achieve the above described objects, a semiconductor device of the present invention comprises a semiconductor element with a thickness of less than 200 xcexcm, a protruding electrode formed on a circuit formation surface of the semiconductor element, sealing resin, for sealing the circuit formation surface and the protruding electrode to cause an upper surface of the protruding electrode to be exposed, and sealing resin for sealing a surface of the semiconductor element opposite to the circuit formation surface, where if the thickness of the sealing resin for sealing the circuit formation surface of the semiconductor element is designated A and the thickness of the sealing resin for sealing the surface of the semiconductor element opposite to the circuit formation surface is designated B, the expression 0.2xe2x89xa6A/Bxe2x89xa61, or 0.2xe2x89xa6B/Axe2x89xa61 is satisfied.
Various modifications are possible to the present invention, and will be understood by one skilled in the art with reference to the claims and embodiments contained herein.